Market forces will take care of this, if needed. If battery price goes up, hydrogen vehicles are favored. What hydrogen vehicles need now is cheaper catalysts for their fuel cells.
Hydrogen-powered vehicles are much, much lighter than battery-driven, so consume less energy in operation. Balanced against that, electrolysing hydrogen has some losses, and braking doesn't regenerate hydrogen you used.
But prices have fallen sharply in recent years, and may continue on down. 2016 is two generations back, in battery years.
Probably future decreases will come from better power density, requiring less physical material for a given capacity, as demand for materials soars. It is remarkable how little lithium there is in a typical Tesla.
Unfortunately, by far the best way to use hydrogen for energy is to use the kind that's already bound to carbon, and unbind it at the point of use, which we're already doing.
Storing it as a comnpressed gas just plain sucks. (Ask NASA and Boeing about that.)
Hydrogen production still needs its own Elon Musk.
It's not even slightly viable unless you get the sweet Toyota $15k credit for hydrogen.
In my country there are exactly 0 hydrogen refuelling stations, I'd need to grab my passport to go refuel =) There are 4 L3 quick chargers 5 minutes away. 4 more 10 minutes away. And I can charge where I park.
I've been watching this space for ... 20 years? All that time Hydrogen cars have been right around the corner.
Nowadays it mostly seems to be people who, for some reason, hate battery electric vehicles and are pointing at the "coming soon" hydrogen vehicles as a reason why they still use an ICE.
Even though a hydrogen powered vehicle IS an EV except that ~80% of the battery is replaced with hydrogen tanks and a fuel cell...
(Yes, Toyota has a prototype car that can run on straight-up hydrogen for like 10 miles at a time)
Hydrogen-powered vehicles are much, much lighter than battery-driven, so consume less energy in operation. Balanced against that, electrolysing hydrogen has some losses, and braking doesn't regenerate hydrogen you used.